<template>
  <div class="el-tree-select">
    <el-select
      style="width: 100%"
      v-model="valueId"
      ref="treeSelect"
      :filterable="true"
      :clearable="true"
      @clear="clearHandle"
      :filter-method="selectFilterData"
      :placeholder="placeholder"
    >
      <el-option :value="valueId" :label="valueTitle">
        <el-tree
          id="tree-option"
          ref="selectTree"
          :accordion="accordion"
          :data="options"
          :props="objMap"
          :node-key="objMap.value"
          :expand-on-click-node="false"
          :default-expanded-keys="defaultExpandedKey"
          :filter-node-method="filterNode"
          @node-click="handleNodeClick"
        />
      </el-option>
    </el-select>
  </div>
</template>

<script setup>
  const { proxy } = getCurrentInstance();

  const props = defineProps({
    /* 配置项 */
    objMap: {
      type: Object,
      default: () => {
        return {
          value: 'id', // ID字段名
          label: 'label', // 显示名称
          children: 'children', // 子级字段名
        };
      },
    },
    /* 自动收起 */
    accordion: {
      type: Boolean,
      default: () => {
        return false;
      },
    },
    /**当前双向数据绑定的值 */
    value: {
      type: [String, Number],
      default: '',
    },
    /**当前的数据 */
    options: {
      type: Array,
      default: () => [],
    },
    /**输入框内部的文字 */
    placeholder: {
      type: String,
      default: '',
    },
  });

  const emit = defineEmits(['update:value']);

  const valueId = computed({
    get: () => props.value,
    set: (val) => {
      emit('update:value', val);
    },
  });
  const valueTitle = ref('');
  const defaultExpandedKey = ref([]);

  function initHandle() {
    nextTick(() => {
      const selectedValue = valueId.value;
      if (selectedValue !== null && typeof selectedValue !== 'undefined') {
        const node = proxy.$refs.selectTree.getNode(selectedValue);
        if (node) {
          valueTitle.value = node.data[props.objMap.label];
          proxy.$refs.selectTree.setCurrentKey(selectedValue); // 设置默认选中
          defaultExpandedKey.value = [selectedValue]; // 设置默认展开
        }
      } else {
        clearHandle();
      }
    });
  }
  function handleNodeClick(node) {
    valueTitle.value = node[props.objMap.label];
    valueId.value = node[props.objMap.value];
    defaultExpandedKey.value = [];
    proxy.$refs.treeSelect.blur();
    selectFilterData('');
  }
  function selectFilterData(val) {
    proxy.$refs.selectTree.filter(val);
  }
  function filterNode(value, data) {
    if (!value) return true;
    return data[props.objMap['label']].indexOf(value) !== -1;
  }
  function clearHandle() {
    valueTitle.value = '';
    valueId.value = '';
    defaultExpandedKey.value = [];
    clearSelected();
  }
  function clearSelected() {
    const allNode = document.querySelectorAll('#tree-option .el-tree-node');
    allNode.forEach((element) => element.classList.remove('is-current'));
  }

  onMounted(() => {
    initHandle();
  });

  watch(valueId, () => {
    initHandle();
  });
</script>

<style lang="scss" scoped>
  @import '@/assets/styles/variables.module.scss';
  .el-scrollbar .el-scrollbar__view .el-select-dropdown__item {
    padding: 0;
    background-color: #fff;
    height: auto;
  }

  .el-select-dropdown__item.selected {
    font-weight: normal;
  }

  ul li .el-tree .el-tree-node__content {
    height: auto;
    padding: 0 20px;
    box-sizing: border-box;
  }

  :deep(.el-tree-node__content:hover),
  :deep(.el-tree-node__content:active),
  :deep(.is-current > div:first-child),
  :deep(.el-tree-node__content:focus) {
    background-color: mix(#fff, $--color-primary, 90%);
    color: $--color-primary;
  }
</style>
